<template>
    <view id="_root" :class="(selectable ? '_select ' : '') + '_root'" :style="containerStyle">
        <slot v-if="!nodes[0]" />
        <!-- #ifndef APP-PLUS-NVUE -->
        <node v-else :childs="nodes" :opts="[lazyLoad, loadingImg, errorImg, showImgMenu, selectable]" name="span" />
        <!-- #endif -->
        <!-- #ifdef APP-PLUS-NVUE -->
        <web-view ref="web" src="/static/app-plus/mp-html/local.html" :style="'margin-top:-2px;height:' + height + 'px'" @onPostMessage="_onMessage" />
        <!-- #endif -->
    </view>
</template>

<script>
/**
 * mp-html v2.4.2
 * @description 富文本组件
 * @tutorial https://github.com/jin-yufeng/mp-html
 * @property {String} container-style 容器的样式
 * @property {String} content 用于渲染的 html 字符串
 * @property {Boolean} copy-link 是否允许外部链接被点击时自动复制
 * @property {String} domain 主域名，用于拼接链接
 * @property {String} error-img 图片出错时的占位图链接
 * @property {Boolean} lazy-load 是否开启图片懒加载
 * @property {string} loading-img 图片加载过程中的占位图链接
 * @property {Boolean} pause-video 是否在播放一个视频时自动暂停其他视频
 * @property {Boolean} preview-img 是否允许图片被点击时自动预览
 * @property {Boolean} scroll-table 是否给每个表格添加一个滚动层使其能单独横向滚动
 * @property {Boolean | String} selectable 是否开启长按复制
 * @property {Boolean} set-title 是否将 title 标签的内容设置到页面标题
 * @property {Boolean} show-img-menu 是否允许图片被长按时显示菜单
 * @property {Object} tag-style 标签的默认样式
 * @property {Boolean | Number} use-anchor 是否使用锚点链接
 * @event {Function} load dom 结构加载完毕时触发
 * @event {Function} ready 所有图片加载完毕时触发
 * @event {Function} imgtap 图片被点击时触发
 * @event {Function} linktap 链接被点击时触发
 * @event {Function} play 音视频播放时触发
 * @event {Function} error 媒体加载出错时触发
 */
// #ifndef APP-PLUS-NVUE
import node from './node/node';
// #endif
import Parser from './parser';
import markdown from './markdown/index.js';
import highlight from './highlight/index.js';
import style from './style/index.js';
const plugins = [markdown, highlight, style];
// #ifdef APP-PLUS-NVUE
const dom = weex.requireModule('dom');
// #endif
export default {
    name: 'mp-html',
    data() {
        return {
            nodes: [],
            // #ifdef APP-PLUS-NVUE
            height: 3
            // #endif
        };
    },
    props: {
        markdown: Boolean,
        containerStyle: {
            type: String,
            default: ''
        },
        content: {
            type: String,
            default: ''
        },
        copyLink: {
            type: [Boolean, String],
            default: true
        },
        domain: String,
        errorImg: {
            type: String,
            default: ''
        },
        lazyLoad: {
            type: [Boolean, String],
            default: false
        },
        loadingImg: {
            type: String,
            default: ''
        },
        pauseVideo: {
            type: [Boolean, String],
            default: true
        },
        previewImg: {
            type: [Boolean, String],
            default: true
        },
        scrollTable: [Boolean, String],
        selectable: [Boolean, String],
        setTitle: {
            type: [Boolean, String],
            default: true
        },
        showImgMenu: {
            type: [Boolean, String],
            default: true
        },
        tagStyle: Object,
        useAnchor: [Boolean, Number]
    },
    // #ifdef VUE3
    emits: ['load', 'ready', 'imgtap', 'linktap', 'play', 'error'],
    // #endif
    // #ifndef APP-PLUS-NVUE
    components: {
        node
    },
    // #endif
    watch: {
        content(content) {
            this.setContent(content);
        }
    },
    created() {
        this.plugins = [];
        for (let i = plugins.length; i--; ) {
            this.plugins.push(new plugins[i](this));
        }
    },
    mounted() {
        if (this.content && !this.nodes.length) {
            this.setContent(this.content);
        }
    },
    beforeDestroy() {
        this._hook('onDetached');
    },
    methods: {
        /**
         * @description 将锚点跳转的范围限定在一个 scroll-view 内
         * @param {Object} page scroll-view 所在页面的示例
         * @param {String} selector scroll-view 的选择器
         * @param {String} scrollTop scroll-view scroll-top 属性绑定的变量名
         */
        in(page, selector, scrollTop) {
            // #ifndef APP-PLUS-NVUE
            if (page && selector && scrollTop) {
                this._in = {
                    page,
                    selector,
                    scrollTop
                };
            }
            // #endif
        },

        /**
         * @description 锚点跳转
         * @param {String} id 要跳转的锚点 id
         * @param {Number} offset 跳转位置的偏移量
         * @returns {Promise}
         */
        navigateTo(id, offset) {
            id = this._ids[decodeURI(id)] || id;
            return new Promise((resolve, reject) => {
                if (!this.useAnchor) {
                    reject(Error('Anchor is disabled'));
                    return;
                }
                offset = offset || parseInt(this.useAnchor) || 0;
                // #ifdef APP-PLUS-NVUE
                if (!id) {
                    dom.scrollToElement(this.$refs.web, {
                        offset
                    });
                    resolve();
                } else {
                    this._navigateTo = {
                        resolve,
                        reject,
                        offset
                    };
                    this.$refs.web.evalJs('uni.postMessage({data:{action:"getOffset",offset:(document.getElementById(' + id + ')||{}).offsetTop}})');
                }
                // #endif
                // #ifndef APP-PLUS-NVUE
                let deep = ' ';
                // #ifdef MP-WEIXIN || MP-QQ || MP-TOUTIAO
                deep = '>>>';
                // #endif
                const selector = uni
                    .createSelectorQuery()
                    // #ifndef MP-ALIPAY
                    .in(this._in ? this._in.page : this)
                    // #endif
                    .select((this._in ? this._in.selector : '._root') + (id ? `${deep}#${id}` : ''))
                    .boundingClientRect();
                if (this._in) {
                    selector.select(this._in.selector).scrollOffset().select(this._in.selector).boundingClientRect();
                } else {
                    // 获取 scroll-view 的位置和滚动距离
                    selector.selectViewport().scrollOffset(); // 获取窗口的滚动距离
                }
                selector.exec((res) => {
                    if (!res[0]) {
                        reject(Error('Label not found'));
                        return;
                    }
                    const scrollTop = res[1].scrollTop + res[0].top - (res[2] ? res[2].top : 0) + offset;
                    if (this._in) {
                        // scroll-view 跳转
                        this._in.page[this._in.scrollTop] = scrollTop;
                    } else {
                        // 页面跳转
                        uni.pageScrollTo({
                            scrollTop,
                            duration: 300
                        });
                    }
                    resolve();
                });
                // #endif
            });
        },

        /**
         * @description 获取文本内容
         * @return {String}
         */
        getText(nodes) {
            let text = '';
            (function traversal(nodes) {
                for (let i = 0; i < nodes.length; i++) {
                    const node = nodes[i];
                    if (node.type === 'text') {
                        text += node.text.replace(/&amp;/g, '&');
                    } else if (node.name === 'br') {
                        text += '\n';
                    } else {
                        // 块级标签前后加换行
                        const isBlock =
                            node.name === 'p' ||
                            node.name === 'div' ||
                            node.name === 'tr' ||
                            node.name === 'li' ||
                            (node.name[0] === 'h' && node.name[1] > '0' && node.name[1] < '7');
                        if (isBlock && text && text[text.length - 1] !== '\n') {
                            text += '\n';
                        }
                        // 递归获取子节点的文本
                        if (node.children) {
                            traversal(node.children);
                        }
                        if (isBlock && text[text.length - 1] !== '\n') {
                            text += '\n';
                        } else if (node.name === 'td' || node.name === 'th') {
                            text += '\t';
                        }
                    }
                }
            })(nodes || this.nodes);
            return text;
        },

        /**
         * @description 获取内容大小和位置
         * @return {Promise}
         */
        getRect() {
            return new Promise((resolve, reject) => {
                uni.createSelectorQuery()
                    // #ifndef MP-ALIPAY
                    .in(this)
                    // #endif
                    .select('#_root')
                    .boundingClientRect()
                    .exec((res) => (res[0] ? resolve(res[0]) : reject(Error('Root label not found'))));
            });
        },

        /**
         * @description 暂停播放媒体
         */
        pauseMedia() {
            for (let i = (this._videos || []).length; i--; ) {
                this._videos[i].pause();
            }
            // #ifdef APP-PLUS
            const command = 'for(var e=document.getElementsByTagName("video"),i=e.length;i--;)e[i].pause()';
            // #ifndef APP-PLUS-NVUE
            let page = this.$parent;
            while (!page.$scope) page = page.$parent;
            page.$scope.$getAppWebview().evalJS(command);
            // #endif
            // #ifdef APP-PLUS-NVUE
            this.$refs.web.evalJs(command);
            // #endif
            // #endif
        },

        /**
         * @description 设置媒体播放速率
         * @param {Number} rate 播放速率
         */
        setPlaybackRate(rate) {
            this.playbackRate = rate;
            for (let i = (this._videos || []).length; i--; ) {
                this._videos[i].playbackRate(rate);
            }
            // #ifdef APP-PLUS
            const command = 'for(var e=document.getElementsByTagName("video"),i=e.length;i--;)e[i].playbackRate=' + rate;
            // #ifndef APP-PLUS-NVUE
            let page = this.$parent;
            while (!page.$scope) page = page.$parent;
            page.$scope.$getAppWebview().evalJS(command);
            // #endif
            // #ifdef APP-PLUS-NVUE
            this.$refs.web.evalJs(command);
            // #endif
            // #endif
        },

        /**
         * @description 设置内容
         * @param {String} content html 内容
         * @param {Boolean} append 是否在尾部追加
         */
        setContent(content, append) {
            if (!append || !this.imgList) {
                this.imgList = [];
            }
            const nodes = new Parser(this).parse(content);
            // #ifdef APP-PLUS-NVUE
            if (this._ready) {
                this._set(nodes, append);
            }
            // #endif
            this.$set(this, 'nodes', append ? (this.nodes || []).concat(nodes) : nodes);

            // #ifndef APP-PLUS-NVUE
            this._videos = [];
            this.$nextTick(() => {
                this._hook('onLoad');
                this.$emit('load');
            });

            if (this.lazyLoad || this.imgList._unloadimgs < this.imgList.length / 2) {
                // 设置懒加载，每 350ms 获取高度，不变则认为加载完毕
                let height = 0;
                const callback = (rect) => {
                    if (!rect || !rect.height) rect = {};
                    // 350ms 总高度无变化就触发 ready 事件
                    if (rect.height === height) {
                        this.$emit('ready', rect);
                    } else {
                        height = rect.height;
                        setTimeout(() => {
                            this.getRect().then(callback).catch(callback);
                        }, 350);
                    }
                };
                this.getRect().then(callback).catch(callback);
            } else {
                // 未设置懒加载，等待所有图片加载完毕
                if (!this.imgList._unloadimgs) {
                    this.getRect()
                        .then((rect) => {
                            this.$emit('ready', rect);
                        })
                        .catch(() => {
                            this.$emit('ready', {});
                        });
                }
            }
            // #endif
        },

        /**
         * @description 调用插件钩子函数
         */
        _hook(name) {
            for (let i = plugins.length; i--; ) {
                if (this.plugins[i][name]) {
                    this.plugins[i][name]();
                }
            }
        },

        // #ifdef APP-PLUS-NVUE
        /**
         * @description 设置内容
         */
        _set(nodes, append) {
            this.$refs.web.evalJs(
                'setContent(' +
                    JSON.stringify(nodes).replace(/%22/g, '') +
                    ',' +
                    JSON.stringify([
                        this.containerStyle.replace(/(?:margin|padding)[^;]+/g, ''),
                        this.errorImg,
                        this.loadingImg,
                        this.pauseVideo,
                        this.scrollTable,
                        this.selectable
                    ]) +
                    ',' +
                    append +
                    ')'
            );
        },

        /**
         * @description 接收到 web-view 消息
         */
        _onMessage(e) {
            const message = e.detail.data[0];
            switch (message.action) {
                // web-view 初始化完毕
                case 'onJSBridgeReady':
                    this._ready = true;
                    if (this.nodes) {
                        this._set(this.nodes);
                    }
                    break;
                // 内容 dom 加载完毕
                case 'onLoad':
                    this.height = message.height;
                    this._hook('onLoad');
                    this.$emit('load');
                    break;
                // 所有图片加载完毕
                case 'onReady':
                    this.getRect()
                        .then((res) => {
                            this.$emit('ready', res);
                        })
                        .catch(() => {
                            this.$emit('ready', {});
                        });
                    break;
                // 总高度发生变化
                case 'onHeightChange':
                    this.height = message.height;
                    break;
                // 图片点击
                case 'onImgTap':
                    this.$emit('imgtap', message.attrs);
                    if (this.previewImg) {
                        uni.previewImage({
                            current: parseInt(message.attrs.i),
                            urls: this.imgList
                        });
                    }
                    break;
                // 链接点击
                case 'onLinkTap': {
                    const href = message.attrs.href;
                    this.$emit('linktap', message.attrs);
                    if (href) {
                        // 锚点跳转
                        if (href[0] === '#') {
                            if (this.useAnchor) {
                                dom.scrollToElement(this.$refs.web, {
                                    offset: message.offset
                                });
                            }
                        } else if (href.includes('://')) {
                            // 打开外链
                            if (this.copyLink) {
                                plus.runtime.openWeb(href);
                            }
                        } else {
                            uni.navigateTo({
                                url: href,
                                fail() {
                                    uni.switchTab({
                                        url: href
                                    });
                                }
                            });
                        }
                    }
                    break;
                }
                case 'onPlay':
                    this.$emit('play');
                    break;
                // 获取到锚点的偏移量
                case 'getOffset':
                    if (typeof message.offset === 'number') {
                        dom.scrollToElement(this.$refs.web, {
                            offset: message.offset + this._navigateTo.offset
                        });
                        this._navigateTo.resolve();
                    } else {
                        this._navigateTo.reject(Error('Label not found'));
                    }
                    break;
                // 点击
                case 'onClick':
                    this.$emit('tap');
                    this.$emit('click');
                    break;
                // 出错
                case 'onError':
                    this.$emit('error', {
                        source: message.source,
                        attrs: message.attrs
                    });
            }
        }
        // #endif
    }
};
</script>

<style>
/* #ifndef APP-PLUS-NVUE */
/* 根节点样式 */
._root {
    padding: 1px 0;
    overflow-x: auto;
    overflow-y: hidden;
    -webkit-overflow-scrolling: touch;
}

/* 长按复制 */
._select {
    user-select: text;
}
/* #endif */
</style>
